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Does Flour Go Bad? Things You Need To Know.

I learn more every day about how to handle foods the right way, and I thought I knew whether or not flour goes bad.

Does flour go bad?

Yes, and sometimes it even starts out bad. Let me explain.

Flour is a processed natural grain, and it spends a lot of time in the fields, in factories, vats, silos, and in processing units, which means it’s exposed to a lot of surfaces…that means germs.

One thing flour is NOT is heated high enough to kill E. Coli, an illness-causing bacteria before it gets to your kitchen.

But AFTER you cook with your flour (to 160F/71C), be it baking or in sauces or gravies, it kills the germs that can make you sick.

But that means one very important thing, and I’m about to make you sad.

You can’t lick the beaters, spatula, or bowl anymore. There, I said it. 

If you were tasting the batter or dough here and there, as we bakers are wont to do, and you didn’t feel very good the next day, eating contaminated raw dough might be why.

And there were outbreaks in recent years that put a lot of people in the hospital. 

So, you don’t necessarily need to throw all of your flour out forever, you just need to not put it in your mouth before it’s been cooked.

Just like eggs.

Avoid the dastardly duo of raw eggs and raw flour, and you are on your way to a more healthy kitchen experience.

But let’s look at more on how to tell if flour goes bad, does flour expire, how to best store flour, and more.

Table Of Contents

What is flour?

Flour is a processed product of grinding wheat, corn, rice, nuts, or seeds until it resembles a fine powder.

It comes in different varieties, but a few common types are all-purpose flour, coconut flour, whole-wheat flour, bread flour, corn flour, almond flour, and even rice flour.

This kitchen staple is a default ingredient in most baked goods such as bread, cakes, and pie crusts. 

Other flour varieties, like all-purpose flour, are good to use as a thickener for sauces, soups, and stews.

If you want to unlock other valuable information surrounding flour, take this comprehensive guide with you!

Does flour go bad?

Yes, flour can go bad, whether it becomes stale and loses freshness, bugs get into it, it smells bad from absorbing refrigerator or pantry odors, or it becomes moldy (usually in humid climates or moisture gets to the bag). 

Flour seems like one of those pantry staples that might last forever.

I thought the same but then I learned the hard way that flour does go bad. 

Store-bought flour usually has a “best-before,” “best-by,” or “better if used by,” on its container, which means the baking product is probably safe to use even if the best-by date has lapsed. 

So, if the “best-by” date has passed it doesn’t mean that you can’t use the flour.

It just means that it may not be as fresh AND that you should check to make sure it hasn’t gone bad.

BUT, and it’s a big but: the shelf life of your flour depends on its variety and how it’s stored.

And of course, how does your flour look, smell and taste when you go to use it?

Does flour expire?

Yes, flour has its expiration date and can become rancid like any other baking product.

According to King Arthur Flour,  flour’s shelf life changes depending on what type it is and how it’s stored in the kitchen. 

To guide you, bear these essential points in mind.

  • Regular flour should last six to eight months past its printed date.
  • Rice flour tends to last for six to eight months past its printed date.
  • Corn flour lasts for up to 12 months past its printed date.
  • Potato flour lasts for up to eight months past its printed date. 
  • Whole wheat flour lasts for four to six months when kept properly. 
  • Self-rising flour tends to last for up to six months. 
  • Corn flour lasts for up to two years when stored properly. 
  • All-purpose flour has a shelf life of six to eight months in the pantry. You can extend it to a year by storing it in the fridge and about a year in the freezer.

Can I use expired flour?

The answer is yes, you can use it past the expiration date but you need to inspect it first.

So what will happen if you’re using expired flour?

From King Arthur Flour:

“What to look for: The flour should look just as it did the day you bought it. If it looks yellow or gray; shows signs of mold; if it’s developed hard moisture lumps, or if you see evidence of insects, discard it. In addition, if the flour smells unpleasant (sour, musty, or just plain bad), don’t use it.”

Moldy flour can be dangerous.

When you spot molds in flour, some molds can produce harmful chemicals known as mycotoxins.

Via Healthline, moldy flour may harm your health, and these mycotoxins can cause vomiting and diarrhea.

Throw away any flour you have that looks or smells moldy.

Pro tip: To avoid mold growth, make sure to keep your flour away from moisture. Place a kitchen towel down on your countertop before putting your bag of flour down to help ensure that the bag isn’t setting in a wet spot that will soak through to the bottom of the bag. A soggy bottom can create a moldy area that you don’t see from the top of the open bag. This is also a good reason to transfer flour to airtight canisters.

How to store flour

Keeping your flour at room temperature is fairly safe as it’s considered a shelf-stable ingredient

If it’s unopened, leave it as is, but if you have already used some of it, place the remaining flour in an airtight container and keep it in a cool and dry place, preferably in the pantry. 

By doing this, you’ll be able to preserve the freshness of your flour as well as protect it from dust and moisture, and hopefully away from pantry moths and weevils.

If you want to increase your flour’s shelf life, consider refrigerating or freezing it. 

Cook’s Illustrated ran some freezing tests on all-purpose flour and found that the frozen flour worked just as well as never-frozen flour, but to make sure it comes up to room temperature before baking with it, or it won’t rise and the texture may not be the same.

To keep from refreezing flour and possibly changing the texture over time with freezer burn, separate your flour into freezer baggies or into an airtight container that you can get to quickly, remove what you need, and immediately return the container to the freezer without letting it sit out.

How to tell if flour has gone bad

Flour indeed has a long shelf life, but it doesn’t mean it’ll last forever.

It’s important to know its condition before mixing it with your other ingredients to avoid baked goods that taste less fresh than they should, taste rancid (I made a rum cake once with walnuts that had gone rancid; so embarrassing).

So how to tell if the flour has gone bad?

It’s simple–by using your senses!

1. Sniff the flour

To know whether your stored flour is still safe to use, it’s best if you use your sense of smell. 

Open the flour container or bag and do a sniff test.

The fat in flour oxidizes with exposure to air over time and can cause it to go rancid, which smells a bit like paint. Toss it if you have a reaction of disgust when you smell it.

Or if it smells musty or sour, this is a clear sign that it has reached its end.

When in doubt, throw it out.

Pro tip: Keep in mind that fresh flour has a neutral odor. Sometimes if flour has been stored in the fridge, like baking soda, it will absorb the fridge odors. This can translate into the flavor of your baked goods, so best to replace the flour and start with fresh.

2. Check the appearance

Another simple method to tell if your flour went bad is to check its appearance. 

Typically, if your flour looks discolored, moldy, or you can see bugs or bug “shells”, throw it all away.

And molds may appear if you let the flour get exposed to water or moisture.
 
If that’s the case, throwing away the flour is also the best thing to do.

The bottom line

Storing your flour properly is one of the many ways to ensure its freshness.

But in case you’re in doubt about that bag of flour in your kitchen pantry, look for the red flags! 

If you spot flour with a discolored look or off smell, then it’s the right time to say goodbye and throw it into the trash.

I kept several rather pricey flours (cassava and arrowroot) in my fridge for a long time (years) because I was too stubborn to throw them away, and they looked fine but they smelled stale when I went to use them.

I finally tossed the bags because I hate wasting other ingredients just to say I saved a few bucks on the flour.

You deserve good things, fresh foods, and self-care. Get a fresh bag of flour for your next delicious recipe!

And remember: don’t lick the beaters, the bowls, or the spatula so you don’t get sick.

Check out these FAQs we have on other flour topics to help you: